1. Field of the Invention
The present invention relates generally to the design of refrigerators and refrigeration equipment. In particular aspects, the invention relates to magnetic seals for refrigerator doors and thermal breakers used in refrigerator cabinets.
2. Description of the Related Art
It is of primary importance in refrigeration design to provide positive and secure sealing for the closures of a refrigerator and freezer. If the seal around the closure is not secure and substantially free from fluid leakage, significant amounts of cold air will escape, and it will be difficult to maintain the contents of the refrigerator or freezer at a desired temperature. The seal around the closure is the area where the most cool air escapes the refrigerator and results in the greatest energy loss.
Most conventional magnetic refrigerator door sealing assemblies use magnetic elements within or behind the door gasket to cause the gasket to seal against a portion of the refrigerator cabinet. In a common type of sealing assembly, the magnetic elements within the gasket are attracted to a portion of the outer metal shell of the refrigerator cabinet. Examples of this type of sealing arrangement are described in U.S. Pat. Nos. 2,914,819; 3,077,644; 3,461,610; 3,468,449; and 4,653,819.
In other door sealing arrangements, the door gasket seals against a thermal breaker on the refrigerator cabinet. Thermal breakers are desirable to insulate the refrigerated air inside of the refrigerator cabinet against the outside air. The materials used to form the thermal breakers are plastic or another non-magnetic material that is less conductive of heat than metal. The magnetic elements associated with the door gasket are attracted to complimentary magnetic elements concealed within the thermal breaker assembly. Examples of thermal breaker arrangements are found in U.S. Pat. Nos. 4,732,432; 5,269,099; 5,476,318 and 6,056,383. While thermal breakers are highly desirable, there is a problem associated with their long term use. When the refrigerator ages and/or is subjected to wear and weight placed upon the door, the door may begin to sag from the hinges or hang askew. When this occurs, the magnets can become easily misaligned and do not close onto the proper portion of the breaker. In the worst cases, when the door is closed, the north or south pole of some or all of the magnetic elements in the door gasket become lined up with the portion of the magnetic element in the breaker that is of the same polarity. When this occurs, the magnetic elements repel one another, thereby causing an improper seal. Sealing of the door is prevented by magnetic repulsion of the gasket from the breaker so that gaps occur, thus allowing cool air from the compartment of the refrigerator to escape.
Another problem with conventional door breakers stems from the fact that the magnets within the breaker are typically rectangular in cross section. They are sometimes made of metal, but more conventionally are formed of vinyl having one side impregnated with metallic flakes that are then magnetically charged to provide a north and south pole. There is a risk that these magnets might be inadvertently flipped upside down either when the magnet is installed initially or when repairs are made.
A related problem with conventional thermal breaker design is that thermal breakers tend to xe2x80x9csweatxe2x80x9d as condensation gathers on them. A further problem with convention thermal breaker design relates to the number of components that are required to be assembled to compose the breaker. A minimum number of parts would be desirable to minimize costs.
It would be desirable to have devices and methods that address the problems of the prior art.
Exemplary refrigerator thermal breakers and door seals are described that provide for a floating magnet within the breaker. The floating magnet is capable of lateral movement within a compartment in the breaker. In the case of a misaligned refrigerator or freezer door, the floating magnet will adjust its position within the breaker compartment to become properly aligned with the magnetic elements in the door gasket. Magnetic attraction will assist this adjustment in the breaker magnet. In the exemplary embodiments described herein the floating magnet is asymmetrical so that it cannot be inadvertently installed in a reversed position.
In addition, the exemplary breaker provides a plastic extrusion that retains not only the floating magnet but a post condenser loop element in contact with the outward-facing wall of the breaker. The post condenser loop circulates heated condenser fluid from the refrigeration mechanism along the outward-facing wall of the breaker, thereby helping to keep the breaker above the ambient air dew point and reducing or eliminating xe2x80x9csweatingxe2x80x9d on the breaker. The extrusion is a single molded piece that engages the breaker assembly in a snap-fit manner.